Prevalence and prognostic role of triple-negative breast cancer by race: a surveillance study.

INTRODUCTION: Emerging research suggests a substantially greater prevalence of the adverse triple-negative (TN) subtype (human epidermal growth factor receptor [HER]2(-), estrogen receptor [ER](-), and progesterone receptor [PR])(-)) among black patients with breast cancer. No reports however have been generated from a statewide cancer registry. PATIENTS AND METHODS: The study consisted of all black patients (N = 643) and a random sample of white patients (n = 719) diagnosed with primary invasive breast cancer (2000-2003) listed in the National Cancer Institute-Surveillance Epidemiology and End Results (NCI-SEER) Connecticut Tumor Registry (CTR). HER2 status was obtained from pathology reports submitted to the registry. Remaining data were obtained from the registry database. RESULTS: TN tumors were more prevalent in black compared with white patients (30.8% vs. 11.2%, respectively; P < .001.) There was a 2-fold greater frequency of ER(-) and PR(-) phenotypes among black patients, but HER2 status did not differ by race. Patients with lobular cancer were less likely to have TN breast cancer compared with patients with ductal tumors (odds ratio [OR] = 0.23; 95% confidence interval [CI], 0.10-0.58). Among patients with regional disease, black patients exhibited increased risk of death (relative risk [RR] = 2.71; 95% CI, 1.48-4.97) independent of TN status. No survival disparity was found among patients with local disease. DISCUSSION: These registry-based data corroborate reports that TN breast cancer varies substantially by race and histologic subtype. A survival disparity among patients with advanced disease, but not local disease, casts some doubt on TN status as an explanation for differences. CONCLUSION: More research is warranted to understand why black patients with advanced breast cancer may be at increased risk for death whether or not their tumors express the TN phenotype.

Patterns of HER2 testing in the management of primary breast cancer.

BACKGROUND: Women with invasive breast cancer should be tested for human epidermal growth factor receptor-2 (HER2) status at the time of diagnosis. To date, no population-based patterns of use studies have examined demographic and clinicopathologic factors associated with decisions by clinicians to test patients. METHODS: We reviewed summary pathology reports submitted to the Connecticut Tumor Registry for all Black/African American (B/AA) women (n=644) and a 7% random sample (n=720) of White women diagnosed in 2000-2003 with primary invasive breast carcinoma. Receipt of a HER2 test (yes vs. no) was examined in relation to patient race, age, socioeconomic status, year of diagnosis, estrogen receptor (ER) status, tumor grade, lymph node status, size and stage at diagnosis. RESULTS: A greater proportion of tumors from B/AA patients were tested compared to those of White women (69.5% vs. 61.9%, p<0.05). Tumors of patients under the age of 60 were 1.50-times more likely than older women to have been tested, and B/AA women were 1.40-times more likely than White patients to be tested. HER2 testing was more likely to be observed when information also was reported about ER status (OR=15.9, p<0.001), tumor grade (OR=2.28, p<0.05), tumor size (OR=2.16, p<0.05), and lymph node status (OR=2.06, p<0.05). CONCLUSIONS: Variation in which breast cancer patients received HER2 testing appears to reflect expectations about a woman's prognosis. Discrepancies in receipt of testing deserve further study as current guidelines call for all tumors to be assessed in order to adequately characterize prognosis and determine eligibility for HER2-targeted therapy.